Summary: This subwoofer amp worked great at first, it provided a good signal to my in-wall Polk Audio subwoofer as expected. Then it just stopped amplifying the signal after about 5 months of usage. It was already past time for Amazon's usual returns, so I contacted the seller via Amazon's system, and they were very responsive. They sent a replacement unit within a few days. The new one works fine out of the box, and my system sounds great again.
Summary: I am running this amp to power two CSW-155 Polk in-wall subs in my home theater. This thing will knock things off the walls if you don't have them secured. I was apprehensive about in-wall subs, but I almost lost it when they came to life for the first time. I am glad I went with the Polk in-wall sub solution. Price is a killer after you do two 800.00 subs and a 700.00 amp, but hey it's only money right.